Multi-purpose acid compositions

ABSTRACT

The invention relates to solutions containing acidic compositions that have a pH of less than 1, are non-caustic to human tissue and are safe for human ingestion. These compositions may be used as the sole or major component of solutions such as cleansers, pharmaceuticals, food preservatives and disinfectants. The acidic compositions may be used in medical, industrial, military and household applications. The invention also relates methods of administering and using the acidic compositions of the invention.

REFERENCE TO RELATED APPLICATIONS

[0001] The application claims priority to U.S. provisional patentapplication, entitled “Multi-Purpose Acid Compositions,” Serial No.60/116,628, filed Jan. 19, 1999.

BACKGROUND

[0002] 1. Field of the Invention

[0003] The present invention relates to acid compositions that areuseful in food, medical, commercial and military industries and also asgeneral household products. These compositions have a low pH, arerelatively non-corrosive to metals, do not harm skin and are safe foruse in food and beverages. The invention also relates to formulationsthat contain these acid compositions and to methods for using suchformulations.

[0004] 2. Description of the Background

[0005] Low pH compositions and solutions containing acidic compositionsare used for various industrial and general household purposes, such ascleaning and sterilizing surfaces and articles of manufacture. Examplesinclude well-known household cleansers and disinfectants, industrialmicrochip production and cleaning agents, and anti-microbials. To workboth effectively and efficiently, these solutions typically containstrong acids or organic solvents, which present health concerns to theuser, may be corrosive to the substances they are designed to clean(e.g. metals) and pose an ecological hazard with respect to disposal.

[0006] There have been a number of efforts aimed at developing lesscorrosive and less toxic acidic products. For example, U.S. Pat. No.4,459,202 is directed to an acidic composition for recovering bituminousproducts from tar sands. Two strong and two weak acids are combined toform an acidic solvent that can be used to remove and recover thebituminous products. The composition is described as being non-corrosiveand less hazardous to handle than other strongly acidic solutions.

[0007] The molecular effect of combining first and second strong acidswith the third and fourth weaker acids forces the weaker acids to act asconjugate bases for the strong acids and to accept hydrogen ions(actually hydronium ions in aqueous solution) from the strong acids. Theresulting acidic solution has a very low pH value, and a large amount offree hydrogen ions. However, the ability of this strong acidiccomposition to effectively function as a solvent may sometimes requiremore acid than would be considered safe or non-hazardous to humantissue. Moreover, there is no suggestion that this composition can beused in other applications, such as in products which come into contactwith food. In fact, the composition cannot be used in connection withfood and drink, as one or more of its components are not listed on theU.S. Food and Drug Administration list of substances consideredgenerally recognized as safe (GRAS).

[0008] Various formulations using multiple acid compositions aredisclosed in U.S. Pat. Nos. 4,675,120, 4,970,014, 4,970,015 and5,019,288. Each of these compositions is described as either useful forwell-acidizing, tertiary oil recovery, removing rust from metal,cleaning aluminum, radiator cleaning, boiler and heat exchangercleaning, or copper cleaning. These compositions are described asgenerally non-corrosive to metal and relatively inert when contactedwith human tissue. In addition, U.S. Pat. No. 4,483,887 describes amultiple acid solution useful for metal plating. U.S. Pat. No. 4,477,364describes a multiple acid solution useful for cleaning glassware.

[0009] Although these acid-based solutions may be effective for thevarious described purposes, a major drawback is that certainformulations can cause skin irritation. For example, studies conductedusing atopical skin disinfectant containing the core composition of U.S.Pat. No. 4,459,202 found that the product caused reddening of the skinand a burning sensation. Similar reddening of the skin and burningsensation resulted with a cleaning solution containing the core acidcomposition of U.S. Pat. No. 4,459,202. As such, these acid compositionscannot be safely used in products where skin contact is a possibility.In addition, such compositions cannot be used in products associatedwith foods or beverages. Further, many of these compositions require amultiplicity of components, leading to increased production costs.

[0010] U.S. Pat. No. 5,512,200 is directed to a multiple acidcomposition described as non-irritating to the skin and useful as acomponent of products such as cleansers, cosmetics and pharmaceuticalagents. However, at least one of the components is not considered GRAS.Thus, despite the relatively inert nature of this composition, it cannotbe used in foods or drinks, or in products associated with foods ordrinks.

[0011] There is therefore a need for acid compositions comprising aminimum number of component acids, all of which components are approvedby the Food and Drug Administration as GRAS, with broad utility forcleaning, sterilizing and anti-microbial uses that are effective,non-toxic and safe for use with food and food-related products.

SUMMARY OF THE INVENTION

[0012] The invention overcomes the problems and disadvantages associatedwith current strategies and designs and provides novel low pHcompositions useful in medical, military, industrial and householdsettings. These acid compositions can be used as the sole or corecomponent of solutions including cleansers, anti-microbial agents,disinfectants, decontaminants, pharmaceuticals, cosmetics, anti-odoragents and sterilants.

[0013] The low pH compositions of the present invention are safe for useas either the sole or major component of solutions including, but notlimited to, disinfectants, cleansers, sterilizers, cosmetics, andpharmaceutical agents, and can be used in industrial, medical, militaryand general household settings. The compositions of the presentinvention are safe not only for use in products which contact humanskin, but also for use in ingestible products.

[0014] One embodiment of the invention is directed to an acid solutionfor inhibiting microbial growth comprising an aqueous acidic corecomposition which makes up 50% to 100% of the solution. The acidic corecomposition consists of acids that are safe for use in food and drinkproducts and food- and drink-associated products (i.e. GRAS substances).The acidic core composition may be prepared by admixing from about zeroto about 25%, by volume, of a first acid, preferably between about 0.1%to about 15%, and more preferably between about 0.5% and about 10%, withbetween about 1% and about 25%, by volume, preferably between about 2%and about 15%, and more preferably between about 5% and about 10%, of asecond acid to produce a first acidic composition.

[0015] The first acid is an inorganic acid that dissociates nearly tocompletion in water. The second acid is an inorganic acid less strongthan the first, having a dissociation constant of less than about 10⁻¹.A second acidic composition is formed by mixing from about 0.5% to about20%, by weight, preferably from about 2% to about 15%, and morepreferably from about 6% to 10%, of an organic hydroxy acid with water.The organic hydroxy acid has a greater chelating capability (generallyat least twice) or iron binding efficiency as one or the other of thefirst and second inorganic acids. Acids with at least twice the ionbinding efficiency of the inorganic acids include, for example, ascorbicacid, citric acid, lactic acid, malic acid and tartaric acid.

[0016] The two acidic compositions or solutions are then mixed toproduce an acid core composition that inhibits microbial growth and issafe for use in food products. This composition preferably has a pH ofless than one, yet will not adversely react with human tissue.

[0017] In a preferred embodiment, the first acid is hydrochloric acid,the second acid is phosphoric acid, and the organic hydroxy acid iscitric acid. Generally, the quantities of the first acid will balancethe quantity of the second acid such that less of the first acid will berequired when using more of the second acid. A maximum quantity of thesecond acid is that amount which will require the addition of no firstacid when admixed with the organic hydroxy acid to produce the low pHcomposition of the invention.

[0018] The acid composition of the present invention maintains the lowpH and non-toxic qualities of conventional acidic compositions, yet,unlike these compositions, is safe to use in food and food-associatedproducts, such as paper for packaging and wrapping food, foodcontainers, food preserving agents and ingestible products.

[0019] In contrast, acids used in a number of conventional products,such as, for example, hydrofluoric, sulfuric, nitric, chloric,perchloric, chlorous, hydrofluoric, hydrosulfuric, fumaric, oxalic,phthalic, tartaric, acetic, acrylic, benzoic and carbonic acid, are notgenerally recognized as safe, and none are federally approved for use iningestible products or products contacting ingestible products. Further,as many of the conventional acid-based solutions are toxic, disposal andhandling of such compositions require special measures not necessarywhen utilizing compositions of the invention.

[0020] Another embodiment of the invention is directed to apharmaceutical compound comprising a three acid composition, the threeacid composition comprising: a first acid, wherein the first acid is aninorganic acid that dissociates nearly to completion in water; a secondacid, wherein the second acid is an inorganic acid less strong than thefirst inorganic acid and has a dissociation constant of less than about10⁻¹; a third acid, wherein the third acid is an organic hydroxy acidwhich is weaker than the first and second acids, has a greater chelatingcapacity, generally at least twice, of either first or second acid, andhas a dissociation constant of from about 10⁻¹ to 10⁻⁵; and apharmaceutical agent. Preferably, the three acids are GRAS acids.

[0021] Another embodiment of the invention is directed to a compositionfor processing food items comprising a three acid preservativeconsisting of: first inorganic GRAS acid that dissociates nearly tocompletion in water; a second inorganic GRAS acid less strong than thefirst acid and having a dissociation constant of less than about 10⁻¹;and a third GRAS acid, the third GRAS acid being an organic hydroxy acidthat has at least twice the chelating efficiency as either of theinorganic acids. Preferably, the organic hydroxy acid is weaker than thefirst and second acids and has a dissociation constant of from about10⁻¹ to 10⁻⁵. An especially preferred food processing compositioncomprises hydrochloric, phosphoric and citric acids.

[0022] Another embodiment of the invention is directed to a method ofpreserving food comprising the addition of a three acid preservativecomposition to a food substance. The three acid preservative compositioncomprises: a first GRAS acid which is an inorganic acid that dissociatesnearly to completion in water; a second GRAS acid, the second GRAS acidbeing an inorganic acid less strong than the first GRAS acid and havinga dissociation constant of less than about 10⁻¹; and a third GRAS acid,the third GRAS acid being an organic hydroxy acid weaker than the firstand second GRAS acids, with chelating capability at least twice as greatas either or both of the first and second GRAS acids and a dissociationconstant from about 10⁻¹ to 10⁻⁵.

[0023] Another embodiment of the invention is directed to a method fordecontaminating surfaces comprising contacting the surface with an acidcomposition of the invention comprising: a first GRAS acid, wherein thefirst GRAS acid is an inorganic acid that dissociates nearly tocompletion in water; a second GRAS acid, wherein the second GRAS acid isan inorganic acid less strong than the first inorganic acid and has adissociation constant of less than about 10⁻¹; and a third GRAS acid,wherein the third GRAS acid is an organic hydroxy acid weaker than thefirst and second GRAS acids, but being at least twice as efficient aseither or both of the first and second inorganic acids in its chelatingability and having a dissociation constant of from about 10⁻¹ to 10⁻⁵.

[0024] Another embodiment of the invention is directed to a method fortreating a surface to inhibit microbial growth on the surface comprisingcontacting the surface with a three acid composition according to theinvention.

[0025] Other objects and advantages of the invention are set forth inpart in the description which follows, and in part, will be obvious fromthis description, or may be learned from practice of the invention.

DESCRIPTION OF THE INVENTION

[0026] As embodied and broadly described herein, the present inventionis directed to low pH acidic compositions that are generally recognizedas safe. Compositions according to the invention are safe for use infood, beverage, or other ingestible products and do not irritate theskin. The present invention is useful in industrial, medical, military,and household applications. Medical applications include use on humansand animals. The invention also relates to formulations containing theacidic compositions of the invention, applications of thesecompositions, and to methods of making and using these compositions.

[0027] Many of the acidic compositions currently used in industrial,medical, military and household settings present health hazards to theuser and are corrosive with prolonged exposure to the surfaces theycontact. Use of these compositions often requires special protectiveclothing and application methods. Additionally, disposal of these toxicproducts in a manner which ensures the safety of the environment andpersonnel is costly and time consuming. Although some conventionalcompositions are less caustic to skin and, overall, less hazardous tothe user than others, they are, nonetheless, not safe for use in foodand beverages or in other ingestible products.

[0028] An acid composition that can be safely handled and applieddirectly to human skin has been discovered which, unlike conventionalacid-based compositions, uses a minimum number of ingredients, all ofwhich are federally approved for use in food and drink products andfood- and drink-associated products. Compositions of the invention arealso applicable for industrial, military and general household uses. Inaddition to being suitable for use on and by humans, the presentinvention is also appropriate for animals. The compositions of theinvention are effective and may be used over a wide range oftemperatures, including room temperature. Thus, the present inventionprovides an advantage over sterilants which require a power source orenergy, such as heat (autoclaving). Moreover, acid compositions of theinvention have a shelf life of one year or greater when stored atambient temperature.

[0029] One embodiment of the invention is directed to a low pH acidcomposition comprised only of GRAS substances. GRAS substances are thosesubstances which are approved for use in food, beverages and otheringestible products, and in products which contact these materials.Specifically, these substances, listed at 21 C.F.R. Part 182 and Part184, are recognized by the FDA as safe for use in foods, beverages andingestible products, and in products associated with foods andbeverages. Such substances are generally considered non-carcinogenic. Assuch, the compositions of the invention are safe to use in associationwith food and drinks and other ingestible products.

[0030] In a preferred embodiment, three acids are used. The first acidis hydrochloric acid, the second acid is phosphoric acid, and the thirdacid is citric acid. In this embodiment, the first acid of thecomposition, hydrochloric acid, comprises between about zero to about 25volume percent of the final composition, preferably between about 0.1 to20 volume percent, and more preferably between about 5 to about 10volume percent of the final composition. Hydrochloric acid is a stronginorganic acid which dissociates nearly to completion in water. Someparticularity useful acid compositions of the invention contain about0.1%, 0.2%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 8%,10%,12%,14%, 15%, 18%, 20%,21%, 22% and 24% of the first acid.

[0031] The second acid of the composition, phosphoric acid, is also aninorganic acid but is less strong than hydrochloric acid. Phosphoricacid thus functions as a conjugate base and accepts hydrogen ions(actually hydronium ions in aqueous solutions) from the strongerhydrochloric acid. The phosphoric acid comprises between about 0.1 toabout 20 volume percent of the final composition and preferably betweenabout 1 to 15 volume percent, and more preferably between about 5 toabout 10 volume percent of the final composition. Some particularityuseful acid compositions of the invention contain about 0.5%, 1%, 2%,3%, 4%, 5%, 6%, 8%, 10%, 12%, 13%, 14%, 15%, 16% and 18% of the secondacid.

[0032] The third acid is an organic acid (e.g. citric acid) belonging tothe group of hydroxy carboxylic acids and is a weak acid relative tohydrochloric and phosphoric acids. Specifically, citric acid is a6-carbon, tricarboxylic acid. Citric acid preferably comprises betweenabout 1 to about 15 weight percent, preferably between about 5 to about10 weight percent and more preferably between about 6 to about 9 weightpercent of the final composition. Some particularity useful acidcompositions of the invention contain about 0.5%, 1%,2%,3%, 4%,5%,6%,8%, 10%, 12%, 13%, 14%, 15%, 16%, 17% and 18%, by weight, of the organichydroxy acid.

[0033] A preferred embodiment of the improved aqueous acidic compositionof the invention may be prepared by a process involving the followingsteps:

[0034] (1) mixing at room temperature from about 5 to about 10 (mostpreferably 6.60) volume percent hydrochloric acid (HCl being principallyresponsible for the resulting pH) with from about 1 to about 5 (mostpreferably 4.49) volume percent phosphoric acid in a first container fora period of time sufficient to produce a homogenous mixture;

[0035] (2) mixing at room temperature in a second container from about 5to about 10 (most preferably 7.50) weight percent citric acid with fromabout 85 to about 90 percent water for a period of time sufficient toresult in thorough mixing; and

[0036] (3) admixing at room temperature the hydrochloric/phosphoric acidmixture held in the first container into the citric acid/water mixtureof the second container until a homogenous composition results.

[0037] The acid aqueous composition of the present invention isbasically colorless (high concentrations of HCl produce a greenish toyellowish color), has a pH of less than one, will not harm human tissue,and contains only substances approved by the Food and DrugAdministration to be GRAS substances. Thus, the resulting aqueous acidiccomposition is safe for use in food, drink, and other ingestibleproducts. The composition of the present invention is also much lesscorrosive to metals than acid compositions at a similar pH. Delicateinstruments such as, for example, dental instruments, surgical and othermedical instruments, and computer parts, can be effectively cleanedusing an acid composition of the invention without harming the delicatecomponents or parts of the instrument or causing undue wear.

[0038] The acid composition of the present invention may be used aloneor as the base, core or active component in the formulation of othersolutions. Additional ingredients, if desired, may be added to the threeacid composition depending on its intended purpose or application.Substances may be added to the core acid composition, for example, toincrease the retention time of the product on the skin, to give anappealing color or scent to the composition, to produce a specifictexture, or to increase the specificity of application of thecomposition. Additives such as anesthetic agents (e.g. lidocaine), pHindicator dyes and other dyes and contrast agents can be added dependingon the application.

[0039] The compositions of the present invention are suitable for use ina plurality of food industry, household, military, medical andindustrial settings. Just a few potential uses of the compositions ofthe present invention include: cleaning and disinfecting surfaces,instruments, foods and equipment; antimicrobial component for hygieneproducts, preparation of skin surface for injections, topical ointments,creams, gels, inhalants (generally used at concentrations of 5%, 4%, 3%,2%, 1% or less), mouth and eye washes, activation of immune-response(e.g. stimulates non-specific immunity); anti-odorant; cleaning anddisinfecting food items and food processing (e.g. removes coffee and teastains), packaging and storage materials; pH- and/or microbial-controlagent (swimming pools); a detoxifying/decontaminating composition forclean up of chemical spills or hazardous materials (HazMat)(decontamination showers) (eliminates toxic cloud/fumes from acid spillsat various mixtures such as 10:90, 25:75, 60:40, 50:50, 40:60, 75:25 and90:10 mix depending on the acid); manufacture of food processing,packaging and transportation items; detoxifying composition forindustrial settings (i.e. paper mills and other industrial plants, andlaboratories may use HCl and/or sulfuric acids; can treat HCl burns withinvention); industrial showers (acid showers); manufacture ofacid-containing solutions and products (i.e. batteries containing“battery acid” such as sulfuric acid; by mixing with invention, lesstoxic and less fuming); cleaning battery posts; sterilization orpurification of water supply; non-toxic embalming agent;detoxification/deactivation of chemical and biological warfare agents;and cleaning air ducts.

[0040] Specific veterinary, dental and medical applications includewound cleaning and disinfecting, disinfecting and sterilizing floors,surfaces and instruments (dialysis apparatus), topical treatment of skininfection, treatment of topical irritants (poison ivy and poison oak),sterilization of indwelling devices (e.g. catheters, IV drips); anti-STDapplications (i.e. suppositories, creams, gels, condoms, mouthwashes,douches); treatment of burns, sunburns, ear infections, insect bites,jellyfish stings, anti-coagulant, treatment of medical waste, andanti-fungal agents (e.g. anti-jock itch treatment, prevention ortreatment of athlete's foot).

[0041] The invention can also be used as an anti-odorant to neutralizeammonia-based odors/wastes, biological specimens, chemical toilets,animal bedding and diapers. It may be used as an underarm deodorant. Inconnection with food, it may be used to spray produce, clean anddisinfect food transport containers and fluid lines or any surfacecoming in contact with food and food serving materials. It may beapplied to seafood as a deodorizer and be used to spray live animals orto spray meat before wrapping, etc. As an antibacterial, anti-fungal andsporicide, it may be used, for example, as an acidifier in home canning.

[0042] With respect to military applications, the invention may be usedto decontaminate chemical warfare agents on personnel and surfaces, andgiven its broad spectrum of activity, is ideal for incorporation intobandages and sponges. The invention may be incorporated into a missileor other delivery device as a countermeasure to deactivate chemicalwarfare or biological agents (e.g. protein toxins such as anthrax,botulism and E. coli) delivered by or contained in another weaponsystem. It may be delivered to a broad contaminated area through the useof a fog/smoke generating device, crop-dusting or firefighting aircraft.

[0043] Applications also include use as a non-toxic embalming agent,anti-scale build-up and treatment of water supplies, electrolyte sportsdrink, treatment of personal items such as toothbrushes or hairbrushes,safety showers for certain industries using acids, acid spill or acidcloud clean up. It may be used as a silver or chrome polish, to removeoxidation build-up on heat exchangers, pipes and water heaters, todescale sinks, water storage tanks, showers and the like to removebarnacles, or to clean concrete. It may be used as a fixative for fabricdyes (pH indicator dyes bonded to cotton fabrics—dye retained aftermachine laundering; also may be used in wearable pH indicator garmentswhich are acid or base sensitive). It may be used as a preservative forfoods, biological specimens, forensic specimens and biological specimensand lumber. It may be used as a buffer for noxious solutions or toinhibit the corrosive properties of bleaching solutions. Furtherapplications include etching aluminum or porcelain, and use as ananti-freeze or water purifier. Because the invention is compatible withpH indicator dyes, solution efficacy can be visually determined. Also,solutions have the potential for repeated re-use (i.e. can be recycled).

[0044] Another embodiment of the invention is directed to apharmaceutical agent or compound containing the acid composition of thepresent invention. As will be clear to those of skill in the art,various substances may be added to the aqueous acidic composition ofthis invention as desired to produce a pharmaceutical agent. The terms“pharmaceutical agent” or “pharmaceutical compound” as used herein areused in their broadest possible sense and include, but are not limitedto, medications and all types of therapeutic agents, whether takenorally, parenterally, topically, or by any other route. Usefulsubstances which may be added to produce a pharmaceutical agent include,but are not limited to, anesthetic agents, alcohols, creams, gels, aloevera, vitamin E, PFP (polyfluorenated perfluorate, e.g. TEFLON,FOMBLIN), moisturizers, emollients, surfactants, humectants, scents,colorants, glycerin, propylene glycol, emulsifiers, wetting agents, pHindicator dyes, medically-relevant dyes, contrasting agents, andcarriers known in the art. Uses of the pharmaceutical agents orcompounds formulated with the three acid composition include, but arenot limited to, deodorants, mouthwashes, topical antimicrobial ointmentfor wounds, and compositions for the treatment of a wide variety ofmaladies, including dry skin, wrinkles, acne, age spots, sunburn,infections (viral, bacterial and fungal), insectbites and rashes. Thepharmaceutical agent may be appropriate for use on mucous membranes,including the mouth and eyes. The pharmaceutical agent or compound canbe brought into contact with the surface to be treated either directlyor via applicators, including, but not limited to, sponges, towelettesand pads.

[0045] Another embodiment of the invention is directed todecontamination agents containing acid compositions of the invention.These agents are particularly useful in military and industrialapplications. These decontamination agents provide protection from, ordirectly inactivate, a variety of toxic chemical agents, such as thoseused in chemical warfare, farming, and lawn care. Such toxic chemicalsinclude, but are not limited to, insecticides, pesticides, mustards,nerve agents, blister agents, cholinesterases and cholinesteraseinhibitors in general. Additionally, decontamination agents according tothe invention are effective in the inactivation of biologically toxicmolecules such as those used in warfare. Biologically toxic moleculesinclude, but are not limited to, aflatoxins, biological toxins,exotoxins, endotoxins, poisons, phytotoxins, insect and animal venomsand mycotoxins. Because of the non-caustic nature of the acidcompositions of the present invention, these decontamination agents maybe applied either directly to the skin, or may be applied to clothing orother materials that come in contact with skin. Thus, the presentinvention is suitable for use by first-responders in decontaminatingphysical surfaces, treating wounds in humans or animals, and/ordeactivating chemical agents including nerve agents.

[0046] In a preferred decontamination compound, a three acid compositionis made into a reactive topical skin protectant which may be mixed witha perfluorinted polyether grease vehicle, a water-based vehicle, orother suitable vehicle. Use of alternative vehicles allows forflexibility in application of the topical protectant. The resultingdecontamination/protection barrier is active over a broad temperaturerange of from about −10° C. to about 50° C., and is stable for one yearor longer when stored at ambient temperatures.

[0047] Another preferred embodiment is directed to a decontaminationcompound in which the acid composition is incorporated into towelettesor sponges. The use of these towelettes or sponges allows for safe andrapid detoxification of organophosphate compounds (e.g. nerve agents),as well as viruses, bacteria and toxic molecules. The towelettes orsponges are easily carried by personnel and used by first-responders indecontamination steps. The towelettes or sponges are active over a broadtemperature range of from about −10° C. to about 50° C., and have ashelf life of one year or longer.

[0048] Another embodiment of the invention is directed to cleansingagents containing the acid composition. These cleansing agents include,but are not limited to, glass cleansers, metal cleansers, householdcleaning solutions (kitchen and bathroom), and solutions to removeoxidation build-up from pipes and water heaters and heat exchangers.

[0049] In this use of the invention, detergents, soaps, scents or strongacids may be added as needed to the acid composition. In a preferredcleansing agent, hydrochloric acid is added to the acid composition inratios ranging from about 0.1 parts to 30 parts (by volume) of the acidcomposition to produce a solution suitable for use as a metal cleaner.Addition of more hydrochloric acid reduces the time required forcleaning; however, this may result in a product which irritates skin.

[0050] Another embodiment of the invention is directed to the use of theinvention as an antimicrobial agent such as a disinfectant or sterilant.These disinfectants and sterilants may be used, for example, tosterilize drinking water, disinfect surfaces, treat wounds, sterilizehair care and manicure equipment, sterilize dental equipment, sterilizehospital clean rooms, sterilize tissue culture hoods in laboratories,and sterilize biological waste. The three acid composition of thepresent invention may also be used in cleaning or sterilizing containersused in the transportation and storage of food and drink, such as trucktanks, vats and fluid lines.

[0051] Substances including, but not limited to, perfumes, aerosols,dyes, alcohols, reducing agents, anesthetic agents, oxidizing agents,amines, amides, surfactants, creams, gels and other acids may be addedto the compositions of the present invention as needed for a particularapplication.

[0052] Another embodiment of the invention is directed to a compositionfor processing food comprising a three acid preservative consisting of afirst inorganic GRAS acid that dissociates nearly to completion inwater, a second inorganic GRAS acid having a dissociation constant ofless than about 10⁻¹, and a third GRAS acid being an organic acid weakerthan the first and second acids, and having a dissociation constant offrom about 10⁻¹ to 10⁻⁵. An especially preferred food processingcomposition comprises hydrochloric, phosphoric and citric acids.

[0053] Food processing compositions of the present invention may besuitable for decontaminating food items, such as, for example, meats,fruits or vegetables. In a preferred embodiment, the composition isapplied to fruits and/or vegetables to remove or effectively destroyresidual pesticides. The food processing composition may also besuitable for use as a de-odorize for seafood and as an antimicrobialtreatment for meat products.

[0054] Another embodiment of the invention is directed to a method ofpreserving food comprising the addition of an acid preservativecomposition to a food substance, the acid preservative compositioncontaining a first GRAS acid, the first acid being an inorganic acidthat dissociates nearly to completion in water; a second GRAS acid, thesecond acid being an inorganic acid less strong than the first inorganicacid and having a dissociation constant of less than about 10⁻¹; and athird GRAS acid, the third acid being an organic acid weaker than thefirst and second acids, the third acid having a dissociation constant offrom about 10⁻¹ to 10⁻⁵.

[0055] The above formulations and applications are intended to merelyillustrate the wide range of utility of the compositions describedherein and are not intended to be an exhaustive listing of all possibleformulations and uses of compositions according to the invention. Also,as the list of substances approved by the U.S. Food and DrugAdministration to be Generally Regarded As Safe (GRAS) is revised, sowill be the acids available for use in the compositions of theinvention. As will be clear to those of skill in the art, compositionsthat are safe for human ingestion or contact are likewise safe foringestion or contact by other animals.

[0056] The following examples are offered to illustrate embodiments ofthe present invention, but should not be viewed as limiting the scope ofthe invention.

EXAMPLES Example 1 Preparation of Aqueous Acid Composition

[0057] A typical antimicrobial solution can be prepared by firstdissolving the solid citric acid in deionized water, admixing withphosphoric acid and then adding the required amount of 10N or 12Nhydrochloric acid. The amount of the dissolved acids and deionized watermay be precalculated to achieve the following range of concentration ofthe individual acids: citric, 6-10% (by weight), phosphoric acid, 5-10%(by volume), and hydrochloric acid, 0.1-5% (by volume).

[0058] An acid composition according to the invention was prepared usingthe following recipe.

[0059] Container #1

[0060] 170 ml of 75-80% concentrated phosphoric acid was added to 250 mlof 12N hydrochloric acid (which is approximately 28-32%). The mixturewas thoroughly stirred. Ventilation was required as there were fumesfrom each acid and from the mixture.

[0061] Container #2:

[0062] 0.6 lbs (9.6 oz.) of granular citric acid was thoroughly mixed in0.8 gallons (102 oz.) of water until dissolved after which container #1containing the phosphoric/hydrochloric acid mixture was added andthoroughly mixed. The resulting acid composition consisted ofapproximately one gallon. Fumes from the resulting mixture weresubstantially eliminated and the pH was approximately 0.07.

Example 2 Acid Composition as an Antimicrobial Solution

[0063] An E. coli C600 bacterial strain was obtained from a commercialsource. This bacterium was grown at 37° C. overnight in 500 ml ofBrain-Heart Infusion broth (Difco), previously sterilized in anautoclave (121° C., 15 psi, 15 minutes). After the bacterial culturereached mid log phase, organisms were centrifuged (˜5,000 rpm) in 50 mlcentrifuge tubes (Corning). The bacterial pellet was washed twice in 10mM imidazole, 150 mM NaCl (pH 7.2), and once in distilled water beforeresuspending in distilled water to approximately 1.4×10⁹ colony formingunits per ml (cfu/ml).

[0064] Three sets of serial 10 fold dilutions ranging from undiluted to10⁻⁹ of the acid composition generated in Example 1 were then made insterile 1.5 ml eppendorf tubes using sterile distilled water. A specificvolume (100 μl) of the previously made bacterial suspension was added to100 μl of each dilution in each of the three sets of serial 10 fold acidcomposition dilutions.

[0065] The first set of bacteria and acid composition dilutions wereincubated for 6 minutes at room temperature. The incubated cells wereimmediately centrifuged at 5,000 rpm for 30 seconds and the supernatantdiscarded. Each bacterial pellet from each dilution was resuspended 200μl of sterile distilled water and placed into separate plastic petridishes. Sterile molten Brain-Heart Infusion (BHI) agar (˜55° C.) wasadded to each petri dish containing the bacteria. Plates were allowed tosolidify on the bench and were inverted and incubated at 37° C. untilobservable growth was evident. Bacterial colonies were counted andrecorded as cfu/ml.

[0066] The same procedure was followed for the second and third sets ofacid composition dilutions containing 100 μl aliquots of bacterialsuspension. However, the second set was incubated for one hour and thethird set was incubated for three hours. After washing, cells werewashed with sterile distilled water, plated, and the plates incubated at37° C. for 16-20 hours. The effectiveness of different dilutions of acidcomposition with relation to time, against the E. coli strain C600 isshown in Table 1. TABLE 1 Effectiveness of Acid Composition as anAntimicrobial Agent on E. coli Strain C600 Time (minutes) Dilution CFUon Plate Log Reduction* Bacterial Control 100% Water 5 × 10¹⁰ cfu/ml 0 6Undiluted 0 ˜10 6 10⁻¹ >5000 (TNTC) 0 6 10⁻² >5000 (TNTC) 0 6 10⁻³ >5000(TNTC) 0 60 Undiluted 0 ˜10 60 10⁻¹ 0 ˜10 60 10⁻² >5000 (TNTC) 0 6010⁻³ >5000 (TNTC) 0 180 Undiluted 0 ˜10 180 10⁻¹ 0 ˜10 180 10⁻² 42  ˜6.5180 10⁻³ >5000 (TNTC) 0

[0067] Effective dilutions of the acid composition were 10⁻¹ and 10⁻²for any of the three incubation times listed. All undiluted samples ofthe bacteriocidal agent were effective in reducing the E. coli bacterialculture by 10 logs. At 10⁻¹ dilution, 6 minutes was insufficient time toeffect the bacterial population of E. coli. At 60 and 180 minutes, the10⁻¹ dilution reduced the bacterial culture by 10 logs. At 10⁻²dilution, 60 minutes was not effective in bacterial population reductionwhile 180 minutes was effective in reducing the bacterial count to4.2×10³ cfu/ml.

Example 3 Effectiveness of Acid Composition as an Antimicrobial Agent ofB. subtilis

[0068] The bacterial strain used in this study was Bacillus subtilisstrain #19659 obtained from the American Type Culture Collection (ATCC).This bacterium was grown at 28° C. overnight in 500 ml of sterilizedcomplex medium (BHI broth; Difco). After the bacterial culture reachedmid log phase, organisms were centrifuged (˜5,000 rpm) in 50 mlcentrifuge tubs (Corning). The bacterial pellet was washed two times in10 mM imidazole (150 mM NaCl, pH 7.2) and once in distilled water beforeresuspending in distilled water to approximately 5×10¹⁰ colony formingunits per ml (cfu/ml).

[0069] Three sets of serial 10 fold dilutions ranging from undiluted to10⁻⁹ of the acid composition of Example 1 were made in sterile 1.5 mleppindorph tubes using sterile distilled water. A specific volume (100μl) of the previously made bacterial suspension was added to eachdilution in each of the three sets of serial 10 fold acid compositiondilutions. The first set of bacteria with acid composition dilutions wasincubated for 6 minutes at room temperature. Cells were immediatelycentrifuged at 5,000 rpm for 30 seconds and the supernatant wasdiscarded. Each bacterial pellet from each dilution was resuspended in200 μl of sterile distilled water and placed into separate plastic petridishes. Sterile molten BHI agar (˜55° C.) was added to each petri dishcontaining the bacteria and allowed to solidify. Solidified plates wereinverted and incubated at 28° C. until observable growth was evident.Bacterial colonies were counted and recorded as cfu/ml.

[0070] The same procedure was followed for the second and third sets ofacid composition dilutions containing 100 μl aliquots of bacterialsuspension. However, the second set was incubated for one hour and thethird set was incubated for three hours. After incubation, cells werewashed with sterile distilled water, poured into plates and incubated at28° C. for 16-20 hours. The effectiveness of different dilutions of acidcomposition with relation to time, against the B. subtilis (ATCC #19659)can be seen in Table 2. TABLE 2 Effectiveness of Acid Composition as anAntimicrobial Agent of B. subtilis (ATCC #19659) Time Acid CompositionLog (minutes) Dilution Cfu on Plate Reduction* Bacterial Control 100%Water 1.4 × 109 cfu/ml 0 6 Undiluted 0 ˜9 6 10⁻¹ 0 0 6 10⁻² 0 0 610⁻³ >5000 (TNTC) 0 60 Undiluted 0 ˜9 60 10⁻¹ 0 ˜9 60 10⁻² 0 0 6010⁻³ >5000 (TNTC) 0 180 Undiluted 0 ˜9 180 10⁻¹ 0 ˜9 180 10⁻² 0 ˜9 18010⁻³ >5000 (TNTC) 0

[0071] The effective dilutions of the acid composition against B.subtilis were 10⁻¹ and 10⁻² for all three of the incubation timeslisted. All undiluted samples of the bacteriocidal agent were effectivein reducing the B. subtilis bacterial culture by approximately ninelogs. At 10⁻³ dilution, none of the times tested were effective inreducing the bacterial population.

Example 4 Further Dilutions of Acid Composition

[0072] The bacterial strain used in this study was Bacillus subtilisstrain #19659 from American Type Culture Collection (ATCC). Thisbacterium was grown at 28° C. overnight in 500 ml of sterilized complexmedium (BHI broth from Difco). After the bacterial culture reached midlog phase, organisms were centrifuged (˜5,000 rpm) in 50 ml centrifugetubes (Corning). The bacterial pellet was washed two times in 10 mMimidazole (150 mM NaCl, pH 7.2) and once in distilled water beforeresuspending in distilled water to approximately 2.8×10⁹ colony formingunits per ml (cfu/ml).

[0073] One set of dilutions of the acid composition of Example 1 werethen made which ranged from undiluted, 10⁻¹, 10⁻², and 10⁻³, as well asnine other dilutions between 10⁻² and 10⁻³. All dilutions were made insterile 1.5 ml eppendorf tubes using sterile distilled water. A specificvolume (100 μl) of the previously made bacterial suspension was thenadded to each acid composition dilution. The bacteria and each dilutionof acid composition were incubated for 60 minutes at room temperature.The cells were immediately centrifuged at 5,000 rpm for 30 seconds andthe supernatant was discarded. Each bacterial pellet from each dilutionwas resuspended in 200 μl of sterile distilled water and placed intoseparate plastic petri dishes. Sterile molten BHI agar (˜55° C.) wasadded to each petri dish containing the bacteria. Plates were allowed tosolidify, inverted, and incubated at 28° C. until observable growth wasevident. Bacterial colonies were counted and recorded as cfu/ml. Theeffectiveness of different dilutions of acid composition with relationto time, against the B. subtilis (ATCC #19659) can be seen in Table 3.TABLE 3 Effectiveness of Acid Composition as an Antimicrobial Agent onB. subtilis (ATCC #19659) Time Acid Composition Log (minutes) DilutionCfu on Plate Reduction* Bacterial Control 100% Water 2.8 × 10⁹ cfu/ml 060 Undiluted 0 ˜9 60 10⁻¹ 0 ˜9 60 10⁻² 0 ˜9 60 10^(−2.1) 0 ˜9 6010^(−2.2) 0 ˜9 60 10^(−2.3) 0 ˜9 60 10^(−2.4) 0 ˜9 60 10^(−2.5) 0 ˜9 6010^(−2.6) 0 ˜9 60 10^(−2.7) 2.1 × 10¹ ˜8 60 10^(−2.8) 4.8 × 10⁴ ˜6 6010^(−2.9) 6.3 × 10⁶ ˜3 60 10⁻³ >5000 (TNTC) 0

[0074] Effective dilutions of the acid composition against B. subtiliswere from 10⁻¹ to 10^(−2.6) for the 60 minute incubation time. Onceagain the undiluted sample of the bacteriocidal agent was effective inreducing the B. subtilis bacterial culture by approximately nine logs.

Example 5 Effectiveness of Acid Composition as an Antimicrobial Agentagainst E. coli

[0075] The acid composition of Example 1 was used for the followingtesting. Testing was performed using nalgene tubing ({fraction (1/16)}inch in diameter). A culture of Escherichia coli was passed throughthree 3-inch sections of tubing and allowed to incubate for 15 minutesat room temperature. One section of tubing was rinsed with one ml ofsterile water and the portion of the water remaining in the tube wasallowed to incubate for 15 minutes at room temperature. This wasrepeated using acid composition solution and a 10% solution for theremaining tubing sections. Each section was then rinsed with 0.5 ml ofsterile water and the rinse was assayed for bacteria by plating. TABLE 4Effectiveness of Acid Composition as an Antimicrobial Agent against E.coli cfu/ml* (+/− SD) Tubing Treatment 455 +/− 120 water 2 +/− 2  10%Acid Composition 0 100% Acid Composition

Example 6 Effectiveness of the Acid Composition as an AntimicrobialAgent against S. cerevisiae

[0076] To determine the efficacy of the acid composition against fungalpathogens, the acid composition of Example 1 was used as an antifungalagainst Saccharomyces cerevisiae. Fungal cells were grown and mixed witheither water or various concentrations of acid composition with water(50/50, vol./vol.). These were incubated for 15 minutes at roomtemperature followed by plating to determine viability. Percentsurvival, shown below, represents plate counts relative to the watercontrol. TABLE 5 Effectiveness of Acid Composition as an AntimicrobialAgent against S. cerevisiae % Survival (+/− SEM) Acid CompositionConcentration 102 +/− 22   0% (100% water) 6 +/− 4  10% Acid Composition0 100% Acid Composition

Example 7 Preparation of a BC for Testing Efficacy as DecontaminationAgent

[0077] A base compound (BC) according to the invention was prepared bymixing 200 ml hydrochloric acid (12N), 170 ml phosphoric acid and 125grams citric acid generally as described in Example 1. BC wassupplemented with additives and utilized in the reaction assays asdescribed below. The test compounds produced were made by first formingBC, and then using BC for the direct addition of supplements. Unlessotherwise stated, all additions, mixing, etc. were performed at roomtemperature. Liquids added as supplements at a given percentconcentration refers to the volume to volume ratios of supplement to BC.For solids, the amount was weighed out, added to an aliquot of BC andallowed to dissolve, then added to the BC to achieve the appropriatefinal volume.

Example 8 Inhibition of CW-Mime Agents-Materials and Methods

[0078] Chemical Warfare (CW) agents and CW-like or mime agents include anumber of classes of compounds utilizing different mechanisms of action.One such class, nerve agents, such as diisopropyl fluorophosphate (DFP),inhibits acetylcholinesterase. DFP also inhibits the activity of serineproteases like trypsin. Paraoxan, a DFP-like molecule, (diethylp-nitrophenyl phosphate) has a chemistry similar to DFP. Like DFP,paraoxan inhibits trypsin. Because of the similarity, paraoxan was used,as described below, as a DFP mime or model to study the efficacy of BCand modified forms of BC to inactivate the enzyme-inhibiting ability ofthis agent. In the experiments which follow, trypsin coupled to agarosebeads is used as an assay for paraoxan, using the standard calorimetricassay for trypsin, BAEE (N-benzoly-L-arginine ethyl ester). In additionto testing BC, reactive substances were also introduced into BC to testefficacy in inhibiting paraoxan.

[0079] By identifying agents that can prevent paraoxan from inactivatinga serine protease, decontamination compounds can be identified andfurther developed. The relative safety of paraoxan, the ease of assayfor a serine protease, and the large margin of safety of previouslymanufactured test compounds make paraoxan particularly useful forscreening modified test compounds.

[0080] The ability of paraoxan to inhibit the serine protease trypsinwas assessed by placing an aliquot of paraoxan into distilled water (ata ratio of 1:100, paraoxan:water), followed by mechanical mixing of thesolution. This stock of paraoxan was then used for assays in which 10 μlof this paraoxan stock was mixed with 10 μl of one of the test compoundsof the present invention (see below) and incubated for various timeperiods (5, 15, and 60 minutes). The reactions were stopped by theaddition of 20 μl of 1 M imidazole, 100 mM NaCl, pH 7.8.

[0081] Paraoxan solutions were then incubated with the serine protease,trypsin, and the activity of the trypsin was monitored as describedbelow. A trypsin stock solution was freshly prepared for each experimentby weighing out 10 mg, and resuspending this into 1 ml of ice colddistilled water until use (within 15-30 minutes). Trypsin activity wasassessed by diluting the trypsin stock 100-fold in 10 mM imidazole, 100mM NaCl, pH 7.8, and placing 50 μl of this solution into ELISA wells(three rows per individual test experiment). Paraoxan solutions preparedas described above were added to the trypsin. This was allowed toincubate for 30 minutes at room temperature. A 2-fold serial dilution ofthese mixtures were then performed using 10 mM imidazole, 100 mM NaCl,pH 7.8 for each incubation mixture of trypsin and paraoxan/testcompound. A negative control was also prepared by omitting the additionof the paraoxan, and adding distilled water alone.

[0082] Azocoll (an azo-dye impregnated collagen) was used to detectserine protease activity and was the basis for screening the varioustest compounds. A sample of azocoll was diluted into 10 mM imidazole,150 mM NaCl, pH 7.8 (10 mg/ml) and incubated at room temperature for 15to 30 minutes before use. For distribution of the azocoll into ELISAplate test wells, 200 μl pipette tips were modified by cutting 2 to 3 mmoff of the end of each tip which permitted the azocoll particles to beeasily moved freely into and out of the pipettor. To insure that similaramounts of azocoll were distributed to each test well, the azocollsuspension was mixed prior to withdrawing the aliquots with the modifiedpipette tips, and the pipettor was flushed three times with thesuspension, using the third uptake stroke to obtain the azocoll for eachwell. This volume (100 μll) was placed into each test well containingthe serially-diluted trypsin and paraoxan/test compound mixturesprepared as described above.

[0083] Enzymatic activity was determined by visual inspection of theazocoll particles placed into the ELISA test wells after at least a 30minute incubation period at room temperature. Maximal trypsin activitywas determined by the examination of the negative controls, in whichonly trypsin and water were present. The development of soluble coloredproduct indicated that protease activity had occurred and the maximaldilution of trypsin that could produce this color was taken as 100%trypsin activity. For each individual experiment, comparisons ofactivity were made relative to internal controls prepared for thatexperiment. Any diminution of the dilution of trypsin which could stillproduce a soluble, colored product would indicate that the trypsinactivity had been inhibited. The level of maximum trypsin inhibition wastaken as the paraoxan-water control described above. As was the case forthe control for maximal trypsin activity, this control was performed foreach individual trypsin stock solution preparation for each experimentperformed. In addition, a control for each test compound alone, in theabsence of paraoxan, was performed to insure that any inhibition ofactivity was due to the action of paraoxan, and not the test compounditself.

[0084] Results are expressed as integral numbers which represent theincrease in the well number (or increase in dilution of trypsin) thatprotease activity could be detected. Results are given as wholeintegers, wherein the integer represents x in the expression 2^(X). An xvalue of 0 indicates no change, an x value of 1 indicates that thetrypsin could be diluted by half and activity was detected, an x valueof 2 indicates that the trypsin could be diluted by 4 and activity wasvisible, an x value of 3 diluted by 8, etc. The integer represents themean of each set of results rounded to the nearest whole integer.

[0085] As described below, test compounds were added to solutions todetermine if there was any effect on the extent of paraoxan-inducedtrypsin inhibition. These effects were detected by the development ofsoluble colored product from the azocoll at higher serial dilutions ofthe trypsin solutions relative to the paraoxan-water and trypsinincubation. For example, compositions of the present invention includederivatives of BC which contain oxime reagents. Another test compoundcontains amine. These derivative compositions based upon BC may beuseful in optimizing a decontaminating compound for the destruction ofCW agents and mimes. The results which follow indicate that BC, aloneand in combination with other additives, does in fact effect the abilityof paraoxan to inactivate trypsin.

Example 9 Effectiveness of Permanganate-Containing BC Solution inDeactivating Chemical Warfare Agents

[0086] Permanganate-containing test compounds were produced by theaddition of 0.1, 1 and 10 mM potassium permanganate to BC. Thesecompounds were designated as TC02157-0.1, TC02157-1, and TC02157-10,respectively. Controls compounds or sham compounds consisting of thesesame permanganate concentrations in water were also assessed foractivity and are designated as SC02157-0.1,-1,-10, respectively. Afterincubation with the paraoxan, each solution was supplemented with 1 Mimidazole, 100 mM NaCl (pH 7.8) to bring the pH to 7.8. The solutionswere then added to the freshly prepared trypsin solutions and allowed toincubate. The trypsin solutions containing the paraoxan and testcompound mixtures were then serially diluted, followed by the additionof the trypsin activity indicator, azocoll. After 30 to 60 minutes, theplate wells were inspected for trypsin activity, where a soluble coloredproduct indicated that trypsin activity could be detected through therelease of dye from the insoluble azocoll reagent. Each experimentrepresents the average, rounded to the nearest whole integer, of twosets of ELISA plates with 6 dilution series for each test compound andsham. The data in Table 6 represent the fold increase in trypsinactivity due to the test compound over the trypsin activity treated withparaoxan alone/fold increase in trypsin activity due to the shamcompound over the trypsin activity treated with paraoxan alone (testcompound without permanganate was 1). TABLE 6 Inhibition of theParaoxan-Induced Inactivation of Trypsin by Test CompoundsTC02157-0.1/SC-0.1 TC02157-1/SC-1 TC02157-10/SC-1 Expt 1 2/0 2/0 5/1Expt 2 1/0 2/0 4/1 Expt 3 1/0 1/0 3/1

[0087] Indications from the above experiments (results presented as themean increase for six separate experiments) suggested that the compoundssupplemented with permanganate may serve to increase the ability of testcompounds to inactivate paraoxan, and might serve as the basis forfuture tests of the inactivation of DFP directly. The ability of thesham compound SC-10 to inhibit activity was not expected, however thecombination of BC with the permanganate increased the ability of themixture to inhibit paraoxan activity with over a two-fold increase.

[0088] It was subsequently determined that further increases inpermanganate ions, to values of 50, 100, and 250 mM concentrations, didnot increase the ability of the test compounds to inhibit paraoxanactivity (Table 7). The data in Table 7 represents the fold increase intrypsin activity due to the test compound over the trypsin activitytreated with paraoxan alone/fold increase in trypsin activity due to thesham compound over the trypsin activity treated with paraoxan alone.TABLE 7 Effect of Increasing Permanganate on Test CompoundsTC02157-50/SC-50 TC02157-100/SC-100 TC02157-200/SC-200 5/1 5/2 5/2

[0089] These results suggest that a range of no more than 10 mMpermanganate should is most useful. Studies on the effect of time andtemperature on the activity of the test compounds supplemented withpermanganate were also performed. Experiments were designed to performthe paraoxan test inactivation assays at 4° C. in the test compoundssupplemented with permanganate. No significant differences were found inthe ability to inactivate paraoxan activity at the lower temperatures(not shown).

[0090] A series of time course experiments were decided upon due to thechange in color of test compound solutions over time. For this series oftime course experiments, test compounds were prepared supplemented withpotassium permanganate, and a sequence of experiments were performedover the time course of one month. At days 0, 1, 3, 7, 14, 21, and 28paraoxan inactivation assays were run at room temperature. Test compoundwas stored in a polypropylene bottle at room temperature during thistime period for use in the assays. For any given day, an aliquot of thestored test compound (supplemented with 10 mM permanganate as described)was removed, and two separate sets of test assays were performed on twotrypsin test solutions performed in triplicate as described in methods.The ability of this stored test compound to inhibit paraoxan activity ispresented below, presented as the mean of the activity. TABLE 8 TimeCourse of Activity of Permanganate-Supplemented Test CompoundsTC02157-0.1/SC-0.1 TC02157-1/SC-1 TC02157-10/SC-1 Day 0 3/0 3/0 6/1 Day3 3/0 2/0 4/1 Day 7 2/0 2/0 3/0 Day 14 1/0 1/0 1/0 Day 21 1/0 0/0 −1/0  Day 28 1/0 0/0 −1/−1

[0091] The data shown in Table 8 represent the fold increase in trypsinactivity over the trypsin inhibition by paraoxan alone on a given day,as described in methods. The decrease in the paraoxan-inhibitingactivity of the test compound seen in these experiments indicate thatpermanganate ions may degrade the ability of the test compound toinhibit paraoxan activity. Similar experiments were performed using testcompounds stored at 4° C. and at −20° C. in an attempt to delay orinhibit the reaction. No significant differences were seen in theseexperiments (not shown). Permanganate may be detrimental to the testcompound activity under these conditions. Compounds based on supplementswith permanganate may require a two-step procedure with a rapid mixprior to use.

Example 10 Efficacy of BC Mixed with Other Agents

[0092] The above results show that the test compounds supplemented withpermanganate may serve as the basis for inactivation of DFP directly,however, the functional lifetime of the effectiveness of the compoundsmay have been compromised, as after 7 days a significant decrease ineffectiveness was noted. The following experiments were performed inwhich BC was supplemented with other agents that have previously beenimplicated in extending the shelf-life of test compounds (not shown).Specifically, ZnCl₂ (10 μM), MnCl₂ (10 μM), and diethanolamine (5 μM, 50μM, and 100 μM) were utilized as additives to the test compoundTC02157-0.1 and the sham SC-0.1. These additions to the test compoundwere performed, and the resultant solutions were assayed for longevityas performed above. For the following results, the data are presented interms of the relative difference (if positive) between the highestdilution of trypsin activity detected for the test compound minus thatfound for the sham compound. All ions were used at a concentration of 10mM added in the chloride form. Diethanolamine concentrations of 5, 50,and 500 μM are presented as D5, D50, and D100, respectively, in Table 9below. TABLE 9 Effect of Zn, Mn, and Diethanolamine on the Loss ofActivity of Permanganate-Supplemented Test Compounds TC02157-0.1 +Zn +Mn+D5 +D50 +D100 Day 0 3 3 3 3 3 Day 3 3 2 3 3 3 Day 7 3 2 2 2 2 Day 14 21 1 1 2 Day 21 1 1 1 1 2 Day 28 1 0 1 1 1

[0093] The data shown in Table 9 represent the fold increase in trypsinactivity over the trypsin inhibition by paraoxan alone on a given day,as described above. The results showed that both the ZnCl₂ and MnCl₂ didnot significantly alter the loss of activity after 7 days, however,there was a slight increase in overall activity, possibly due to thedivalent cations and/or their interaction with the permanganate. Nodifference was seen using any of the diethanolamine supplementsdescribed above. Similar results were seen when the experiment wasrepeated after a 14 day incubation. There was a noticeable color changein the solutions supplemented with diethanolamine after this period oftime and a loss of activity. Incubation times of over 21 days, however,indicated that the inhibition of activity might be delayed bydiethanolamine or Zn ions in combination with thepermanganate-supplemented compound.

[0094] These studies indicate that the increase in activity attributedto the permanganate might result in a decrease in efficacy of compoundsaccording to the invention within a short period of time. Concurrentwork with other test compounds containing permanganate relative tocontrol test compounds without permanganate had higher paraoxaninhibiting activities and did not lose this activity over similar timeperiods. In view of this, other supplements to BC were examined. Othersupplements that were found to either show no enhancement ofparaoxan-inhibiting ability or an incompatibility with the test assaysystem include mercaptoethanol, iodoacetamide, iodoacetic acid andthiosulfate ions.

[0095] Further experiments were carried out to test a BC compositioncontaining 1% tert-butanol, 1% hydrogen peroxide, 100 μM ZnCl₂ and 10 mMhydroxylamine. This compound reverses the inhibitory effects of paraoxanon trypsin activity. BC composed of hydrochloric acid, phosphoric acidand citrate (as described in Example 1) was prepared and supplementedwith various concentrations of zinc ions in the form of zinc chloride(0.1, 1, 10, 100 and 200 mM). TABLE 10 Inhibition of Paraoxan-InducedInactivation of Trypsin by Zn-supplemented BCs as a Function of Timeafter Production of Test Compounds Zinc Supplement (mM) 0.1 1 10 100 200Activity, Day 0 2 2 3 1 0 Activity, Day 7 2 2 3 1 0 Activity, Day 21 2 24 1 0 Activity, Day 28 2 2 3 1 0

[0096] Based on this study, it was determined that at very highconcentrations of zinc, some direct inhibition of trypsin activity wasoccurring in this assay system during exposure of the trypsin to thetest compound itself, as the controls containing no paraoxan weresimilarly inhibited, resulting in no differences being detected. Theactivity of the supplement at 10 mM, however, indicates that someaugmentation can be detected. No decrease in activity was seen over thecourse of 28 days. Further experiments indicate that no significantchange in activity occurred over a period of three months (not shown).

[0097] Other cations, such as Ca++, Cu++, Fe+++, Mn++, and Co++ wereassessed for their ability to augment the paraoxan-inhibiting activityof the BCs. For the ions Ca and Mn, the assay system controls werealtered such that these supplements could not be easily assessed due tosome direct inhibition of the trypsin in the absence of paraoxan.Limited augmentation of activity was detected using Fe, Cu and Co;however, the slim increase declined rapidly upon storage.

[0098] BC was prepared and a series of test compounds containing variousamounts of butanol (0.1, 0.5, 1, 5, 10, 20, and 30%/o). Thesebutanol-supplemented compounds were then used in paraoxan inhibitionassays as described previously. For the following results, the integersexpressed are the changes in trypsin dilution with delectable proteaseactivity relative to the unsupplemented BC alone. For these results,each positive integer represents a “1” will increase in trypsin activity(i.e. a two-fold increase). Any diminution in the dilution isrepresented by a similar, negative integer. A “0” indicates no changerelative to the unsupplemented compound. Any positive integer wouldindicate that the ability of paraoxan to inhibit protease activity hasbeen limited by the addition of the supplement. No detectable inhibitionof trypsin activity was detected induced by the butanol in the absenceof paraoxan (not shown). TABLE 11 Effect of Butanol on the Inactivationof Paraoxan-Mediated Effects by Test Compounds Butanol % 0.1 0.5 1 5 1020 33 Activity 0 0 0 1 2 4 5

[0099] The ability of butanol to enhance the paraoxan-inhibitingactivity of the BC at 20 to 33% concentration was seen over a period ofone month (not shown). A shorter chain alcohol, propanol, was thentested in a similar set of experiments. An increase in activity (2-fold)was seen at the 33% concentration, with negligible enhancement of BCactivity.

[0100] No change was noted with time for propanol. No activityenhancement was seen using the shorter chain alcohols ethanol andmethanol (not shown). It should be noted that for butanol, the mixturecan separate upon storage. The test compounds supplemented with butanolwere premixed by shaking prior to distribution for testing.

[0101] Hydrogen peroxide supplemented BCs were prepared at peroxideconcentrations of 0.1, 0.5, 1, 2, and 5%. As presented for the butanoldata above, the integers represent the increase in dilution whichpermitted detection of protease activity. TABLE 12 Effect of HydrogenPeroxide Addition on the Ability of Test Compounds to De- activateParaoxan-Mediated Trypsin Inhibition. Hydrogen Peroxide % 0.1 0.5 1 2 5Activity 0 0 1 1 1

[0102] A kinetic study on the lifetime of any enhancement detected wasperformed for hydrogen peroxide-supplemented compounds. It was noticedthat after 1 day (and later determined that within 2 to 4 hours), nodelectable change was seen in that no enhancement occurred after 2 to 4hours of incubation prior to performing the assay.

[0103] Hydroxylamine hydrochloride was used as a supplement to the BC inconcentrations of 1, 2, 5, 10, and 20% (wt./vol.). The effect ofhydroxylamine is expressed as the change seen relative to BC notcontaining any supplement. TABLE 13 Inactivation of Paraoxan-MediatedInhibition of Trypsin by Hydroxylamine Supplemented BCs Hydroxylamine %1 2 5 10 20 Activity, Day 0 0 0 1 2 1 Activity, Day 45 0 0 2 1 1

[0104] No significant change in this activity has been detected forcompounds stored at room temperature for up to 60 days (not shown). Theoximes 2,3 butanedione monoxime (BDM) and 2-pyridine aldoximemethchloride (PAM) were also tested as supplements to BC. No inhibitionof trypsin activity was seen caused by either of these oxime supplementsalone in the absence of paraoxan. For these investigations, the integersrepresent the differences in dilutions of trypsin that showed proteaseactivity, where positive integers are equivalent to an increase in thedilution of trypsin that still permits the detection of proteaseactivity relative to unsupplemented BC. As in the immediately precedingcases, any positive activity integer would indicate that the ability ofparaoxan to inhibit protease activity has been dampened by the additionof the supplement. BC supplemented with oxime reagents were tested atconcentrations of 0.01%, 0.1%, 0.3%, 0.5%, 1%, 2%, and 5% (weight tovolume). TABLE 14 Effect of Oxime (PAM and BAM) Supplements on theAbility of Test Compounds to Inactivate Paraoxan-Mediated Reactions PAM% 0.01 0.1 0.3 0.5 1 2 5 Activity 0 0 0 1 2 2 2 BDM (%) 0.01 0.1 0.3 0.51 2 5 Activity 0 0 0 0 1 1 0

[0105] In the case of PAM, the ability to inhibit Paraoxan was optimalat a 1% concentration. Similar results were obtained for BDM, howeverthe PAM was more effective at all concentrations tested relative to BDM.The 1% concentrations of both reagents in BC were then supplemented withzinc chloride. No significant enhancement was noted except for the useof 10 mM zinc chloride in conjunction with PAM (not shown). Someincrease in activity could be detected by the addition of the abovesupplements with PAM showing the most increase.

[0106] A new series of compounds were prepared that combined some of thesupplements tested above in BC, using combinations of the supplementsshown to be most effective in enhancing the “decon” activity of the testcompounds in inhibiting the paraoxan-induced inhibition of trypsin. As afirst step, zinc ions at 10 mM concentration were added to testcompounds prepared supplemented with hydroxylamine at a 10%concentration. Results in the table below represent the difference inactivity of this double-supplemented BC relative to the BC containinghydroxylamine alone. A similar set of experiments was performed usingzinc (10 mM) added to butanol-supplemented (30%) BC. A time course ofassessment of activity was performed for the solutions stored at roomtemperature. The data indicate that zinc may enhance the activity of thehydroxylamine while either not affecting or even limiting thebutanol-supplemented BC. No significant differences in this were seenover the time course of one month. TABLE 15 Effect of Zn (10 mM)Addition on the Ability Supplemented Test Compounds to inhibitParaoxan-Mediated Effects Zn + Hydroxylamine Zn + Butanol Activity, Day0 1 0 Activity, Day 1 1 −1 Activity, Day 7 0 0 Activity, Day 14 1 0Activity, Day 21 1 −1 Activity, Day 28 0 0

[0107] As can be seen in the foregoing example, butanol, hydroxylamine,zinc chloride and the oxime 2-pyridine aldoxime methchloride can enhanceinactivation of the ability of compositions according to the inventionto deactivate potentially toxic molecules. The effect of thesesupplements does not decay over time.

Example 11 Use of BC to Inactivate Other Agents

[0108] Solutions according to the invention have been used to kill virusand bacteria. BC at 20, 10 and 5% diluted with distilled water reducedtype 1 polio virus concentration by at least 10⁵. Bacterial assays werealso positive. A 15% strength solution of BC in water for 10 minutesresulted in less than 1% survival for E. Coli LP 1395 cells. ForEnterobacter aerogenes, the survival was less than 0.5% under similarconditions. A 1% solution of BC inactivates botulinum toxin more than99.99% within 1 minute.

[0109] Other embodiments and uses of the invention will be apparent tothose skilled in the art from consideration of the specification andpractice of the invention disclosed herein. All references cited herein,for whatever reason, are specifically incorporated herein by referenceincluding U.S. patent application, entitled “Hypertonic AqueousSolutions of Polybasic Acid Salts” filed contemporaneously herewith. Thespecification and examples should be considered exemplary only with thetrue scope and spirit of the invention indicated by the followingclaims.

1. An acidic solution for inhibiting microbial growth comprising an aqueous acidic core composition, said acidic solution comprising from about 50 to about 100 percent of said acidic core composition, said acidic core composition consisting of acids safe for use in food and drink products and food- and drink-associated products, said acid core composition prepared by the steps of: admixing from about 1 to about 5 volume percent of a first acid, said first acid being an inorganic acid that dissociates nearly to completion in water, with about 5 to about 10 volume percent of a second acid, said second acid being an inorganic acid less strong than said first inorganic acid, said second acid having a dissociation constant of less than about 10⁻¹, to produce a first acidic composition; and admixing from about 6 to about 10 weight percent of a hydroxy acid, having at least twice the chelating capability of said first and second acids, with water to produce a second acidic composition; and admixing said first acidic composition with said second acidic composition to produce said acid core composition having a pH of less than one and wherein said acidic core composition will not react with human tissue.
 2. The acidic solution of claim 1 wherein the first acid is hydrochloric acid.
 3. The acidic solution of claim 1 wherein the second acid is phosphoric acid.
 4. The acidic solution of claim 1 wherein the hydroxy acid is an organic acid.
 5. The acidic solution of claim 1 wherein the hydroxy acid is a weak acid relative to said first and second acids, said hydroxy acid having a dissociation constant of from about 10⁻¹ to 10⁻⁵.
 6. The acidic solution of claim 1 wherein the hydroxy acid serves as a conjugate base to said first inorganic acid.
 7. The acidic solution of claim 1 wherein the first acid of said acidic core composition is safe for use in food and drink products and in food- and drink-associated products.
 8. The acidic solution of claim 1 wherein the second acid of said acidic core composition is safe for use in food and drink products and in food- and drink-associated products.
 9. The acidic solution of claim 1 wherein the hydroxy acid is a hydroxy carboxylic acid.
 10. The acidic solution of claim 9 wherein the hydroxy carboxylic acid is selected from the group consisting of ascorbic, citric, lactic, malic and tartaric acids.
 11. The acidic solution of claim 1 wherein the hydroxy acid is a tricarboxylic acid.
 12. The acidic solution of claim 1 wherein the hydroxy acid consists of at least three carbon atoms.
 13. The acidic solution of claim 1 wherein the hydroxy acid is an acid safe for use in food and drink products and in food- and drink-associated products.
 14. The acidic solution of claim 1 wherein the hydroxy acid is citric acid.
 15. The acidic solution of claim 1 wherein the solution is safe for use in ingestible products.
 16. The acidic solution of claim 1 wherein the solution is safe for use on surfaces that contact ingestible products.
 17. The acidic solution of claim 1 wherein the pH of said solution is less than one.
 18. The acidic solution of claim 1 wherein the solution is nonreactive with human skin.
 19. The acidic solution of claim 1 wherein the acidic core composition is substantially non-corrosive to metals.
 20. The acidic solution of claim 1 wherein the solution is substantially non-corrosive to metals.
 21. A pharmaceutical compound comprising a three acid composition, said three acid composition comprising: a first acid, said first acid being an inorganic acid that dissociates nearly to completion in water; a second acid, said second acid being an inorganic acid less strong than said first inorganic acid and having a dissociation constant of less than about 10⁻¹; and a third acid, said third acid being an organic acid weaker than said first and second acids, said third acid having a dissociation constant of from about 10⁻¹ to 10⁻⁵ and having chelating capability of at least twice said first and second inorganic acids; and a pharmaceutical agent.
 22. The pharmaceutical compound of claim 21 wherein the first, second and third acids are GRAS acids.
 23. The pharmaceutical compound of claim 21 wherein the pharmaceutical agent is selected from the group consisting of a gel, a cream, a surfactant, an emollient, a lotion, and a liquid.
 24. The pharmaceutical compound of claim 21 wherein the compound is safe for human ingestion.
 25. A composition for processing food comprising: a first GRAS acid, said first GRAS acid being an inorganic acid that dissociates nearly to completion in water; a second GRAS acid, said second GRAS acid being an inorganic acid less strong than said first GRAS acid and having a dissociation constant of less than about 10⁻¹; and a third GRAS acid, said third GRAS acid being an organic hydroxy acid weaker than said first and second GRAS acids, said third GRAS acid having a dissociation constant of from about 10⁻¹ to 10⁻⁵, and having chelating capability of at least twice said first and second GRAS acids.
 26. The composition of claim 25 wherein the first GRAS acid is hydrochloric acid, the second GRAS acid is phosphoric acid and the third GRAS acid is citric acid.
 27. A method of preserving food comprising the step of adding a three acid preservative composition to a food substance, said three acid preservative composition comprising: a first GRAS acid, said first GRAS acid being an inorganic acid that dissociates nearly to completion in water; a second GRAS acid, said second GRAS acid being an inorganic acid less strong than said first GRAS inorganic acid and having a dissociation constant of less than about 10⁻¹; and a third GRAS acid, said third GRAS acid being an organic acid weaker than said first and second GRAS acids, said third GRAS acid having a dissociation constant of from about 10⁻¹ to 10⁻⁵, and having chelating capability of at least twice said first and second GRAS acids.
 28. The method of claim 27 wherein the first GRAS acid is hydrochloric acid, the second GRAS acid is phosphoric acid and the third GRAS acid is citric acid.
 29. A method for decontaminating surfaces comprising the step of contacting said surface with a decontaminant comprising a three acid composition, said three acid composition comprising: a first GRAS acid, said first GRAS acid being an inorganic acid that dissociates nearly to completion in water; a second GRAS acid, said second GRAS acid being an inorganic acid less strong than said first GRAS inorganic acid and having a dissociation constant of less than about 10⁻¹; and a third GRAS acid, said third GRAS acid being an organic acid weaker than said first and second GRAS acids, said third GRAS acid having a dissociation constant of from about 10⁻¹ to 10⁻⁵, and having chelating capability of at least twice said first and second GRAS acids.
 30. The method of claim 29 wherein the surface is decontaminated from one or more contaminants selected from the group consisting of a bacteria, a virus, a fungus, an aflatoxin, a biological toxin, an exotoxin, an endotoxin, a poison, a phytotoxin, an insect venom, an animal venom, a mycotoxin, an insecticide, a pesticide, a mustard agent, a nerve agent, a blister agent, a cholinesterase and a cholinesterase inhibitor.
 31. The method of claim 29 wherein the surface is a surface which comes into contact with products used for human consumption.
 32. The method of claim 29 wherein the surface is human tissue.
 33. The method of claim 29 wherein the surface comes into contact with human tissue.
 34. The method of claim 29 wherein the three acid composition is contained within a porous substance.
 35. The method of claim 29 wherein the three acid composition is contained within a sponge.
 36. The method of claim 29 wherein the three acid composition is contained within a towelette.
 37. The method of claim 29 wherein the three acid composition further comprises an agent selected from the group consisting of a foam, a surfactant, an aerosol, a thickening agent, and a gel.
 38. A method for inhibiting microbial growth on a surface comprising contacting said surface with a compound, said compound comprising a three acid composition, said three acid composition comprising a first acid, said first acid being an inorganic acid that dissociates nearly to completion in water; a second acid, said second acid being an inorganic acid less strong than said first inorganic acid and having a dissociation constant of less than about 10⁻¹; and a third acid, said third acid being an organic acid weaker than said first and second acids, said third acid having a dissociation constant of from about 10⁻¹ to 10⁻⁵, and having chelating capability of at least twice said first and second acids.
 39. The method of claim 38 wherein the surface is human tissue.
 40. The method of claim 38 wherein the surface is a human eye.
 41. The method of claim 38 wherein the compound is contained within a sponge.
 42. The method of claim 38 wherein the compound is contained within a towelette.
 43. The method of claim 38 wherein the compound is safe for human ingestion. 